# Copyright 2012-2013 Amazon.com, Inc. or its affiliates. All Rights Reserved.

# Licensed under the Apache License, Version 2.0 (the "License"). You

# may not use this file except in compliance with the License. A copy of

# the License is located at

# http://aws.amazon.com/apache2.0/

# or in the "license" file accompanying this file. This file is

# distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF

# ANY KIND, either express or implied. See the License for the specific

# language governing permissions and limitations under the License.

import os

import sys

import struct

import colorama

def determine_terminal_width(default_width=80):

# If we can't detect the terminal width, the default_width is returned.

try:

from termios import TIOCGWINSZ

from fcntl import ioctl

except ImportError:

return default_width

try:

height, width = struct.unpack('hhhh', ioctl(sys.stdout,

TIOCGWINSZ, '\000' * 8))[0:2]

except Exception:

return default_width

else:

return width

def is_a_tty():

try:

return os.isatty(sys.stdout.fileno())

except Exception:

return False

def center_text(text, length=80, left_edge='|', right_edge='|',

text_length=None):

"""Center text with specified edge chars.

You can pass in the length of the text as an arg, otherwise it is computed

automatically for you. This can allow you to center a string not based

on it's literal length (useful if you're using ANSI codes).

"""

# postcondition: len(returned_text) == length

if text_length is None:

text_length = len(text)

output = []

char_start = (length // 2) - (text_length // 2) - 1

output.append(left_edge + ' ' * char_start + text)

length_so_far = len(left_edge) + char_start + text_length

right_side_spaces = length - len(right_edge) - length_so_far

output.append(' ' * right_side_spaces)

output.append(right_edge)

final = ''.join(output)

return final

def align_left(text, length, left_edge='|', right_edge='|', text_length=None,

left_padding=2):

"""Left align text."""

# postcondition: len(returned_text) == length

if text_length is None:

text_length = len(text)

computed_length = (

text_length + left_padding + len(left_edge) + len(right_edge))

if length - computed_length >= 0:

padding = left_padding

else:

padding = 0

output = []

length_so_far = 0

output.append(left_edge)

length_so_far += len(left_edge)

output.append(' ' * padding)

length_so_far += padding

output.append(text)

length_so_far += text_length

output.append(' ' * (length - length_so_far - len(right_edge)))

output.append(right_edge)

return ''.join(output)

def convert_to_vertical_table(sections):

# Any section that only has a single row is

# inverted, so:

# header1 | header2 | header3

# val1 | val2 | val2

#

# becomes:

#

# header1 | val1

# header2 | val2

# header3 | val3

for i, section in enumerate(sections):

if len(section.rows) == 1 and section.headers:

headers = section.headers

new_section = Section()

new_section.title = section.title

new_section.indent_level = section.indent_level

for header, element in zip(headers, section.rows[0]):

new_section.add_row([header, element])

sections[i] = new_section

class IndentedStream(object):

def __init__(self, stream, indent_level, left_indent_char='|',

right_indent_char='|'):

self._stream = stream

self._indent_level = indent_level

self._left_indent_char = left_indent_char

self._right_indent_char = right_indent_char

def write(self, text):

self._stream.write(self._left_indent_char * self._indent_level)

if text.endswith('\n'):

self._stream.write(text[:-1])

self._stream.write(self._right_indent_char * self._indent_level)

self._stream.write('\n')

else:

self._stream.write(text)

def __getattr__(self, attr):

return getattr(self._stream, attr)

class Styler(object):

def style_title(self, text):

return text

def style_header_column(self, text):

return text

def style_row_element(self, text):

return text

def style_indentation_char(self, text):

return text

class ColorizedStyler(Styler):

def __init__(self):

# autoreset allows us to not have to sent

# reset sequences for every string.

colorama.init(autoreset=True)

def style_title(self, text):

# Originally bold + underline

return text

#return colorama.Style.BOLD + text + colorama.Style.RESET_ALL

def style_header_column(self, text):

# Originally underline

return text

def style_row_element(self, text):

return (colorama.Style.BRIGHT + colorama.Fore.BLUE +

text + colorama.Style.RESET_ALL)

def style_indentation_char(self, text):

return (colorama.Style.DIM + colorama.Fore.YELLOW +

text + colorama.Style.RESET_ALL)

class MultiTable(object):

def __init__(self, terminal_width=None, initial_section=True,

column_separator='|', terminal=None,

styler=None, auto_reformat=True):

self._auto_reformat = auto_reformat

if initial_section:

self._current_section = Section()

self._sections = [self._current_section]

else:

self._current_section = None

self._sections = []

if styler is None:

# Move out to factory.

if is_a_tty():

self._styler = ColorizedStyler()

else:

self._styler = Styler()

else:

self._styler = styler

self._rendering_index = 0

self._column_separator = column_separator

if terminal_width is None:

self._terminal_width = determine_terminal_width()

def add_title(self, title):

self._current_section.add_title(title)

def add_row_header(self, headers):

self._current_section.add_header(headers)

def add_row(self, row_elements):

self._current_section.add_row(row_elements)

def new_section(self, title, indent_level=0):

self._current_section = Section()

self._sections.append(self._current_section)

self._current_section.add_title(title)

self._current_section.indent_level = indent_level

def render(self, stream):

max_width = self._calculate_max_width()

should_convert_table = self._determine_conversion_needed(max_width)

if should_convert_table:

convert_to_vertical_table(self._sections)

max_width = self._calculate_max_width()

stream.write('-' * max_width + '\n')

for section in self._sections:

self._render_section(section, max_width, stream)

def _determine_conversion_needed(self, max_width):

# If we don't know the width of the controlling terminal,

# then we don't try to resize the table.

if max_width > self._terminal_width:

return self._auto_reformat

def _calculate_max_width(self):

max_width = max(s.total_width(padding=4, with_border=True,

outer_padding=s.indent_level)

for s in self._sections)

return max_width

def _render_section(self, section, max_width, stream):

stream = IndentedStream(stream, section.indent_level,

self._styler.style_indentation_char('|'),

self._styler.style_indentation_char('|'))

max_width -= (section.indent_level * 2)

self._render_title(section, max_width, stream)

self._render_column_titles(section, max_width, stream)

self._render_rows(section, max_width, stream)

def _render_title(self, section, max_width, stream):

# The title consists of:

# title : | This is the title |

# bottom_border: ----------------------------

if section.title:

title = self._styler.style_title(section.title)

stream.write(center_text(title, max_width, '|', '|',

len(section.title)) + '\n')

if not section.headers and not section.rows:

stream.write('+%s+' % ('-' * (max_width - 2)) + '\n')

def _render_column_titles(self, section, max_width, stream):

if not section.headers:

return

# In order to render the column titles we need to know

# the width of each of the columns.

widths = section.calculate_column_widths(padding=4,

max_width=max_width)

# TODO: Built a list instead of +=, it's more efficient.

current = ''

length_so_far = 0

# The first cell needs both left and right edges '| foo |'

# while subsequent cells only need right edges ' foo |'.

first = True

for width, header in zip(widths, section.headers):

stylized_header = self._styler.style_header_column(header)

if first:

left_edge = '|'

first = False

else:

left_edge = ''

current += center_text(text=stylized_header, length=width,

left_edge=left_edge, right_edge='|',

text_length=len(header))

length_so_far += width

self._write_line_break(stream, widths)

stream.write(current + '\n')

def _write_line_break(self, stream, widths):

# Write out something like:

# +-------+---------+---------+

parts = []

first = True

for width in widths:

if first:

parts.append('+%s+' % ('-' * (width - 2)))

first = False

else:

parts.append('%s+' % ('-' * (width - 1)))

parts.append('\n')

stream.write(''.join(parts))

def _render_rows(self, section, max_width, stream):

if not section.rows:

return

widths = section.calculate_column_widths(padding=4,

max_width=max_width)

if not widths:

return

self._write_line_break(stream, widths)

for row in section.rows:

# TODO: Built the string in a list then join instead of using +=,

# it's more efficient.

current = ''

length_so_far = 0

first = True

for width, element in zip(widths, row):

if first:

left_edge = '|'

first = False

else:

left_edge = ''

stylized = self._styler.style_row_element(element)

current += align_left(text=stylized, length=width,

left_edge=left_edge,

right_edge=self._column_separator,

text_length=len(element))

length_so_far += width

stream.write(current + '\n')

self._write_line_break(stream, widths)

class Section(object):

def __init__(self):

self.title = ''

self.headers = []

self.rows = []

self.indent_level = 0

self._num_cols = None

self._max_widths = []

def __repr__(self):

return ("Section(title=%s, headers=%s, indent_level=%s, num_rows=%s)" %

(self.title, self.headers, self.indent_level, len(self.rows)))

def calculate_column_widths(self, padding=0, max_width=None):

# postcondition: sum(widths) == max_width

unscaled_widths = [w + padding for w in self._max_widths]

if max_width is None:

return unscaled_widths

if not unscaled_widths:

return unscaled_widths

else:

# Compute scale factor for max_width.

scale_factor = max_width / float(sum(unscaled_widths))

scaled = [int(round(scale_factor * w)) for w in unscaled_widths]

# Once we've scaled the columns, we may be slightly over/under

# the amount we need so we have to adjust the columns.

off_by = sum(scaled) - max_width

while off_by != 0:

iter_order = range(len(scaled))

if off_by < 0:

iter_order = reversed(iter_order)

for i in iter_order:

if off_by > 0:

scaled[i] -= 1

off_by -= 1

else:

scaled[i] += 1

off_by += 1

if off_by == 0:

break

return scaled

def total_width(self, padding=0, with_border=False, outer_padding=0):

total = 0

# One char on each side == 2 chars total to the width.

border_padding = 2

for w in self.calculate_column_widths():

total += w + padding

if with_border:

total += border_padding

total += outer_padding + outer_padding

return max(len(self.title) + border_padding + outer_padding +

outer_padding, total)

def add_title(self, title):

self.title = title

def add_header(self, headers):

self._update_max_widths(headers)

if self._num_cols is None:

self._num_cols = len(headers)

self.headers = self._format_headers(headers)

def _format_headers(self, headers):

return headers

def add_row(self, row):

if self._num_cols is None:

self._num_cols = len(row)

if len(row) != self._num_cols:

raise ValueError("Row should have %s elements, instead "

"it has %s" % (self._num_cols, len(row)))

row = self._format_row(row)

self.rows.append(row)

self._update_max_widths(row)

def _format_row(self, row):

return [str(r) for r in row]

def _update_max_widths(self, row):

if not self._max_widths:

self._max_widths = [len(el) for el in row]

else:

for i, el in enumerate(row):

self._max_widths[i] = max(len(el), self._max_widths[i])